Pair furnace



L MILHOLLAND.

PAIR FURNACE. APPLICATION FILED .IAN.24, I922.

l ygQ, Patented Aug'. 229 1922.

2 SHEETSASHEET l.

ATTE RN EY I. II/IILHOILAND.

PAIR FURNAQE.

APPLICATION FILED IAN.24, I922.

Patented Aug. 22, R922.

2 SHEETS-SHEET 2.

INVNTOR u I be? 5 @wenn P'- i' @atterrit PAIR- FURNACE.

iaiaaeoa Application filed January 24, 1922.

T0 all w 710m t may concern Be it known that l, Join.' lvliLrioiriANn, a citizen ofthe l'lnit'cd tates, residing at Leechhurg. in thc count;Y of Armstrong and Stateif ll'cnnsylvania., have invented new and us 1nl Improvements in Pair Furnaces, of which the following is a specilication.

rihis invention relates to furnaces, and more particular y to what l term a pai r furnace.

One of the main objects of the invention is to provide a furnace which is so constructed that the pairs or bars which are heated preparatorj.v to passing the same throughthe rolls in a. rolling mill, are completely enclosed or enveloped by the products of combustion from the `hre in the furnace so as to prevent oxidizing of the metal and consequent scaling duringv the rolling operation. A further object is to provide a furnace of thc character stated of compara tively simple construction and operation which may be erected at a reasonable cost. Another object is to provide simple and effi cient means for controlling the supply of steam and air to the lire. Further objects will appear from the detailed description.

In the drawings :f-

Figure 1 is a side view of the furnace;

Figure 2 is a horizontal sectional view;

Figure 3 is a central vertical section;

Figure 4 is a fragmentary side view showing the blowing nozzle as applied;

Figure 5 is a vertical section through the blowing nozzle;

Figure 6 is a section taken substantially on line 6-6 of Figure 5.

The furnace includes a casing` 1 which may be constructed of any suitable or preferred refractory material. This casing includes an ash pit 2 positioned beneath grate 8 in a fire hoX 4. A bridge wall 5 extends across the Ere box in rear of grate 3 and is reinforced by a central divider 6 extending from baffle 5 'to a lbaiile wall i' which eX- tends from bottom 8 to top 9 of the furnace. This battle wall is provided. with two openings 10 positioned at opposite sides of member 6, these openings having their edges flush with the inner face of the bottom 6 of the furnace. A baliie wall 11 is provided adjacent to back wall 12 of the furnace, this baliie wall being provided with two openings or ports 18 corresponding to ports 10 but being spaced above the inner face of specification of Leners raient. Patented Aue. 22, 1922.

Serial No. 531,448.

the bottom wall. to leave an escape opening 14 by means of which the products of combustion can escape into a sheet furnace positioned in the rear of casing 1.

@ne side wall 1L of casing 1 is provided with an opening 15 communicating with the lire box t, this opening being normally closed by a door 16 slidable in guide strips 17, any suitable or j areferred means being provided for operatingthis door, such as a cable 18 secured at one end to door 16 and passed over guide pulleys 19, a counterweight 2O being secured on the other end of this cable. lWall 1 is further provided Back wall 12 is cut awajY with two openings 21 communicating with heated are placed in the furnace through thedoor adjacent to bridge 7 and, after being heated to the required temperature, are stacked adjacent to battle wall 11 as to be readily removed through the other opening lWhile the pairs are in the furnace they are completely surrounded and enveloped by the products of combustion which iiow across the lower portion of the space between baflies 7 and 1.1, indicated in Figure 3, the carbon dioxide and other gases which are produced by combustion surrounding and enveloping the pairs so as to prevent access of air to the same when either of the doors 16a is opened. This prevents oxidizingof the pairs and thus eliminates scaling' which occurs when the. pairs are heated in furnaces of the type now cornmonly used in which air can enter the furn nace and come into Contact with the pairs when the furnace door is opened.

To assist in the operation of the furnace Il provide a nozzle 22 which fits into an elbow 23 secured through side wall 1b of the casing 1 beneath grate 3. A tapered valve plug 24; is rotatably mounted in the upper portion of a valve casing 25 from which nozzle 22 eX- tends, and is provided with two bores 26 and 27 disposed to be turned into alignment with corresponding bores 28 and 28a, and 29 and 29, respectively, formed in casing 25. An air supply tube 30a is secured in bore 29a and an air discharge tube 30 is secured in bore 29. A steam supply tube 31a is secured in bore 28a, and bore 28 communicates with space 31 formed between tube 30 and nozzle 22 and providing a discharge space for the steam. Steam and air are simultaneously supplied by means oli tubes 3l and 30', and associated parts, to elbow 23 and are injected into the lire box beneath grate 3 for producing more complete combustion which results in the production of intense heat capable of heating the pairs in the space between bridges 7 and ll, the products of combustion completely surrounding and enveloping the pairs in the manner and for the purpose above stated. A hand Wheel 32 is secured on stem 33 of valve plug 2l so that by turning this hand wheel the supply of air and steam to elbow 28 may be cut off simultaneously thus avoiding any chance of accidentsuch as is apt to occur where the air and the steam are controlled separately, and ffiving a more direct control over the suppl7 oi air and steam.

What I claim is l. In a pair furnace, a casing provided at one end with a lire box, battles extending across said casing adjacent to each end thereof, the baille 'adjacent to the lire box being provided with ports positioned closely adjacent to the bottom olv the casing and the baille remote from the lire bon being pro vided with ports spaced above the bottom of the casing.

2. Ina pair furnace, a casing including a lire box, a bridge positioned at the inner side of the lire box, a bafiie positioned adjacent to said bridge and in spaced relation thereto and extendingthroughout the crossarea ofthe casing, said baille being provided in its lower portion with ports adjacent to the bottom of the casing, and a baille positioned remote 'from the lirst mentioned baf lle and extending throughout the cross-area of the casing, the second mentioned bridge being provided in its lower portion. with ports spaced above the bottom of the casing.

In a pair furnace, a casing provided with a .lire box at one end, a bridge adjacentto the inner side of said lire box, a baille e2;- tending throughout the cross-arca of the casing and positioned adjacent to said bridge, said baille being provided in its lower portion with ports closely adjacent to the bottom of the casing, a divider extending from the bridge to the baille and positioned midway between said ports, and a'second ballie positioned adjacent to the other end of the casing and extending throughout the crossarea thereofJ said second baille being provided with ports spaced above the bottom ol said casing. j

In Vtestimony whereof I alx my signature.

JOHN MILl-IOLLAND. 

